This invention relates to a tonneau cover for use on pick-up trucks, and more particularly relates to a flexible, twistable tonneau cover for pick-up trucks which will withstand off-road driving, without having the tonneau cover fall off the truck.
Pick-up trucks have recently become very popular in the automobile industry. Tonneau covers are popular to put on the backs of pick-up trucks; however, they have not been able to be used on off-road trucks because they were not flexible enough to withstand off-road driving conditions. The box on a pick-up truck is designed to twist with rotational torque in response to the wheels of the truck falling into holes and pits in roads that are experienced in off-road conditions. Conventional tonneau covers are rigid and generally are rigidly secured to the backs of the pick-up trucks, which means that in off-road conditions they will pop off. Ideally, the tonneau cover should also be able to exhibit rotational torque or twisting of the tonneau cover in order to follow the twisting of the truck bed box.
Conventional tonneau covers are made of structural foam, hard fiberglass or other hard structural materials which do not flex. In addition, their attachment means to the truck body bed are rigid placement devices, such that when the truck bed itself twists, the tonneau cover rips its fasteners out and the cover pops off.
Furthermore, it has been found by EPA testing, that the mileage per gallon experienced by a pick-up with a tonneau cover is approximately 1.6 to 1.8 miles per gallon better than the same pick-up truck without a tonneau cover. The aerodynamical advantages of utilizing a tonneau cover would help the automobile industry greatly in meeting the CAFÉ standards for miles per gallon per vehicle.
Therefore, it would be a great advantage to devise a tonneau cover which would be designed to twist or exhibit rotational torque independently from the truck body box so that such a pick-up truck could still have a tonneau cover on it while in off-road conditions.
In accordance with the present invention, there is disclosed a new pick-up truck tonneau cover which is designed to twist or exhibit rotational torque independent from the truck body box. In essence, the new tonneau cover incorporates two advantages. First, an independent suspension attaches it to the vehicle truck body box. Second, it is made of a new type of material. Furthermore, the underside of the tonneau cover, or the xe2x80x9cBxe2x80x9d surface, is made of a snakeskin-like configuration such that the tonneau cover would crumple into a myriad of pieces in the event of a rear-end collision.
The independent suspension mentioned above is accomplished by the use of several spring sockets with preloaded springs so that the tonneau cover can independently ride on springs from the truck body box itself. These springs are described in greater detail hereinbelow.
The new material that is used for the tonneau cover is an energy management, or energy recoverable, foam. This material is a urethane foam having a high recovery factor which is derived from closed cell urethane flexible foam. It is sold under the trademark xe2x80x9cENERFLEXxe2x80x9d available from Woodbridge Foam Group of Mississauga, Ontario, having a North American division located at 1401 Meijer Boulevard in Troy, Mich. This energy management, or energy recoverable, foam is utilized in order to twist and torque to compensate for off-road conditions. While this type of foam has many of the advantages of structural foam which has been used in conventional or prior art tonneau covers, the foam of the instant invention has a recovery factor such that if it is dented or twisted, it exhibits a memory to return it to its original shape without losing any of its integrity or strength.
Lastly, the xe2x80x9cBxe2x80x9d surface is made of numerous scale-like projections and protrusions occurring longitudinally perpendicular to the axis of the truck in order to prevent decapitation of the occupants of the vehicle in the event of a rear-end collision. These scale-like protrusions and projections will act as a crumple zone and burst into a myriad of pieces in the event of a rear-end collision. These concepts will be discussed with greater detail hereinbelow.